The present invention relates to a set for spinal anesthesia.
More particularly, it relates to a set which includes an introducer needle, a spinal needle and a stylet.
Sets for spinal anesthesia of the above mentioned type are known in the art. Usually, during the operation a big bore introducer needle is placed within intraspinal muscles. Then a small bore spinal needle is placed within the introducer needle to prevent its bending and curving, advanced further, and positioned within the subarachnoid space. The stylet which extends through the spinal needle is removed and after the cerebral spinal fluid appears, a syringe with anesthetic is attached to the spinal needle and medicine is injected. In this set, however, the spinal needle positioned through the introducer needle within the subarachnoid space is very unstable. It slides back and forth via the introducer needle.
In my U.S. Pat. No. 5,312,375 it has been proposed to provide means for removably fixing the spinal needle and the introducer needle with one another when the spinal needle enters the subarachnoid space so that the spinal needle is freely movable inside the introducer needle between a plurality of locations, and the means for removably fixing the spinal needle and the introducer needle engages the spinal needle and the introducer needle transversely to the direction of elongation in any of a plurality of positions. Therefore the spinal needle and the introducer needle are fixed with one another in any of a plurality of positions. While this proposal is very efficient, its disadvantage is that the modification of the introducer needle so as to provide in it the corresponding fixing means makes the introducer needle more expensive.